Topic: Reducing Audio File Size

I am interested in reducing the size of my audio files so that I can fit more on my IPOD. I noticed yesterday that, when comparing 2 song files:
-Both songs were about 5 minutes long
-1 file was 2-3 MB
-1 file was 50+ MB

This implies that there are different audio file formats avaialable and that I should be able to adjust my audio searches/saves accordingly to reduce file size and be able to save more on my IPOD.

I have 2 goals:
1. Identify which audio format offers the smallest file size without a significant quality reduction.
2. Ideally, I could download a program to re-write my entire library to change my audio files to the optimal configuration.

They are probably different by Bit Rate, and possibly the same format.

I think that if you use Apple's AAC format 128 kbps Bit Rate for music it is good enough and uses less disk space (and battery) than the equivalent MP3. Others will disagree. Search a bit and you'll find lots of discussions on VBR (variable bit rate) and use of 192 kbps and more.

No need to download anything, iTunes can do it for you. Set the setting you want, right click the song, choose Convert Selection to AAC and delete the old copy of the file.

Have you backed up your iTunes Library this week? If not, you are risking losing your music and playlists....

Thanks for the help. I have only tried your advice on 1 song, but I was able to reduce it in size from 37.1 to 3.4MB. I only plan to use my headphones (no proffesional use of IPOD), so I assume any reduction in quality will not be noticeable.

You might want to try converting to AAC 224 or AAC 256 with VBR enabled and compare the sound quality vs. 128.

I use 128 for tracks that aren't really critical for sound quality, but for classical, I use 224 -- a slightly better sense of space, even on headphones, without too much size increase.

Wow. 37.1 to 3.4MB -- you must have been using Lossless or even WAV.

You're going to free up a LOT of space!

Transitioning from a June 2006 XP Pro Dell E1505 to a Windows 7 Dell XPS 16 received mid-December 2009, and with my first iTunes library created on a June 2003 Inspiron 8500 and hooking up to a 120GB Classic.

Sorry this is my first post, but I've got a 16GB Ipod Touch and I've got 1GB of space left because of my music...

I copied all my music (I hope my old iBook isn't too overloaded) and I selected all my music and clicked *create ACC verison. I've got a few questions though:

Will it delete the MP3s after converting?

Will they all be 192 kps (or whatever)? That's what I have the encoder set for when it copies my cds.

Also, anyone have any idea how long it takes to create 2,665 ACCs?

Do. Not. Do. This.

You cannot accomplish anything useful by transcoding between lossy formats. A lossy encode (mp3, AAC, ogg, wma, etc.) are sort of like a photocopy. Some of the very high and very low frequencies are discarded (these are arguably inaudible), and the remaining audio is approximated using fancy, schmancy mathematical algorithms that use considerably less data to describe each second of audio (this is your bitrate, the higher the bitrate, the more accurate the approximation). You can only achieve an optimal result when you go from a lossless source (wave, FLAC, ALAC, AIFF, the original CD, etc.) to some lossy format, otherwise what you are doing is making an approximation of an approximation. To use the photocopy analogy again, you're making a photocopy of a photocopy, and if you've ever done this much, you ought to know that after so many generations, the result is looking pretty rough. The only semi-practical reason to transcode lossy to lossy is if space is more important than audio quality and you do something like go from 320 kbps to 192 kbps (or lower), and even then you will be better off going back to the original lossless source.

If your music is in mp3 format, leave it in mp3 format, you will do nothing but degrade audio quality by transcoding. It's as good as it can ever be.

I agree with Code Monkey, but if you do convert your files keep the originals or re-rip from CDs. You would be better off managing your media on the iPod using playlists and smart playlists. Smart playlists can be made to rotate music on and off the iPod.

To answer your questions, when you do convert them with iTunes it will not delete the original mp3's, you will have to do it your self. They will be converted to what ever you have iTunes Import Settings set to. How long it will take has to do with how fast your computer is. An older slower system will take more time than a new system with a multicore processor.

They are probably different by Bit Rate, and possibly the same format.

I think that if you use Apple's AAC format 128 kbps Bit Rate for music it is good enough and uses less disk space (and battery) than the equivalent MP3. Others will disagree. Search a bit and you'll find lots of discussions on VBR (variable bit rate) and use of 192 kbps and more.

No need to download anything, iTunes can do it for you. Set the setting you want, right click the song, choose Convert Selection to AAC and delete the old copy of the file.

Hi,
I am also trying to reduce the size of my songs. as i currently only have 2000 songs but they are apparently taking up 13.27GB...i have got an Iphone 16GB. but i would have thought it could hold a lot more songs. i could not find the convert to ACC setting? and when you say select the setting that you want...where would i be able to do that. very amateur when it comes to itunes!
THanks